Problemset - Codeforces

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Codeforces Round (Div. 2)
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number theory

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Problems

#	Name
1986G2	Permutation Problem (Hard Version) brute force, data structures, hashing, math, number theory	2500	x639
1986G1	Permutation Problem (Simple Version) binary search, brute force, combinatorics, data structures, math, number theory	2200	x955
1986E	Beautiful Array greedy, math, number theory, sortings	1700	x6213
1985G	D-Function combinatorics, math, number theory	1600	x7028
1985B	Maximum Multiple Sum brute force, math, number theory	800	x37587
1982D	Beauty of the mountains brute force, data structures, implementation, math, number theory	1700	x5222
1982B	Collatz Conjecture brute force, implementation, math, number theory	1200	x13363
1981D	Turtle and Multiplication constructive algorithms, dfs and similar, graphs, number theory	2400	x1242
1980D	GCD-sequence greedy, implementation, math, number theory	1400	x12066
1979C	Earning on Bets binary search, combinatorics, constructive algorithms, number theory	1200	x16138
1978F	Large Graph data structures, dfs and similar, dsu, graphs, number theory, two pointers	2400	x937
1977C	Nikita and LCM brute force, data structures, dp, greedy, math, number theory, sortings	1900	x5714
1973F	Maximum GCD Sum Queries bitmasks, brute force, dp, implementation, number theory	3100	x175
1968C	Assembly via Remainders constructive algorithms, number theory	1000	x22368
1968A	Maximize? brute force, math, number theory	800	x30672
1967B2	Reverse Card (Hard Version) brute force, math, number theory	2200	x3491
1967B1	Reverse Card (Easy Version) brute force, math, number theory	1400	x11712
1965B	Missing Subsequence Sum bitmasks, constructive algorithms, greedy, number theory	1800	x5835
1957E	Carousel of Combinations brute force, combinatorics, dp, math, number theory	2400	x1106
1955G	GCD on a grid brute force, dfs and similar, dp, implementation, math, number theory	1900	x3930
1954E	Chain Reaction binary search, data structures, dsu, greedy, implementation, math, number theory	2200	x1983
1954C	Long Multiplication greedy, math, number theory	1200	x17572
1950E	Nearly Shortest Repeating Substring brute force, implementation, number theory, strings	1500	x13087
1950D	Product of Binary Decimals brute force, dp, implementation, number theory	1100	x21583
1946E	Girl Permutation combinatorics, dp, math, number theory	2200	x2230
1945H	GCD is Greater brute force, data structures, math, number theory	2600	x555
1945B	Fireworks math, number theory	900	x21021
1934E	Weird LCM Operations brute force, constructive algorithms, number theory	3000	x199
1933D	Turtle Tenacity: Continual Mods constructive algorithms, greedy, math, number theory, sortings	1200	x18743
1933C	Turtle Fingers: Count the Values of k brute force, implementation, math, number theory	1100	x21412
1933B	Turtle Math: Fast Three Task implementation, math, number theory	800	x31029
1932G	Moving Platforms graphs, math, number theory, shortest paths	2300	x931
1932E	Final Countdown implementation, math, number theory	1600	x7388
1932B	Chaya Calendar number theory	1100	x19394
1931G	One-Dimensional Puzzle combinatorics, math, number theory	2000	x2557
1931D	Divisible Pairs combinatorics, math, number theory	1300	x16926
1928E	Modular Sequence brute force, constructive algorithms, dp, graphs, greedy, math, number theory	2300	x1601
1928C	Physical Education Lesson brute force, math, number theory	1600	x7919
1926E	Vlad and an Odd Ordering binary search, bitmasks, data structures, dp, implementation, math, number theory	1500	x10853
1925B	A Balanced Problemset? brute force, greedy, math, number theory	1200	x18902
1920C	Partitioning the Array brute force, math, number theory	1600	x12387
1917D	Yet Another Inversions Problem combinatorics, data structures, dp, implementation, math, number theory	2300	x1698
1916G	Optimizations From Chelsu divide and conquer, dp, number theory, trees	3500	x140
1916B	Two Divisors constructive algorithms, math, number theory	1000	x24428
1916A	2023 constructive algorithms, implementation, math, number theory	800	x24999
1909E	Multiple Lamps bitmasks, brute force, constructive algorithms, math, number theory	2400	x1289
1909D	Split Plus K greedy, math, number theory	1900	x4122
1909B	Make Almost Equal With Mod bitmasks, constructive algorithms, math, number theory	1200	x15041
1907E	Good Triples brute force, combinatorics, number theory	1600	x9353
1906G	Grid Game 2 games, number theory	2900	x157
1902C	Insert and Equalize brute force, constructive algorithms, greedy, math, number theory	1300	x12826
1900D	Small GCD bitmasks, brute force, dp, math, number theory	2000	x3880
1899D	Yarik and Musical Notes hashing, math, number theory	1300	x12719
1899B	250 Thousand Tons of TNT brute force, implementation, number theory	1100	x19006
1899A	Game with Integers games, math, number theory	800	x40487
1896H2	Cyclic Hamming (Hard Version) brute force, dp, fft, math, number theory	3500	x98
1896H1	Cyclic Hamming (Easy Version) brute force, divide and conquer, dp, fft, math, number theory	3400	x87
1884D	Counting Rhyme dp, math, number theory	2100	x2976
1882E1	Two Permutations (Easy Version) brute force, constructive algorithms, greedy, number theory	2400	x977
1881D	Divide and Equalize math, number theory	1300	x15540
1879F	Last Man Standing brute force, data structures, number theory	2800	x479
1878F	Vasilije Loves Number Theory brute force, math, number theory	1900	x3919
1877C	Joyboard math, number theory	1200	x10433
1876B	Effects of Anti Pimples combinatorics, number theory, sortings	1500	x7809
1875C	Jellyfish and Green Apple bitmasks, greedy, math, number theory	1400	x11169
1872C	Non-coprime Split math, number theory	1100	x22578
1866B	Battling with Numbers combinatorics, math, number theory	1400	x7411
1864C	Divisor Chain bitmasks, constructive algorithms, math, number theory	1300	x12973
1859A	United We Stand constructive algorithms, math, number theory	800	x30399
1858C	Yet Another Permutation Problem constructive algorithms, greedy, math, number theory	1000	x22388
1858B	The Walkway brute force, dp, greedy, math, number theory	1500	x10920
1855B	Longest Divisors Interval brute force, combinatorics, greedy, math, number theory	900	x24843
1852A	Ntarsis' Set binary search, math, number theory	1800	x7754
1850F	We Were Both Children brute force, implementation, math, number theory	1300	x17918
1848E	Vika and Stone Skipping brute force, implementation, math, number theory	2600	x758
1848C	Vika and Price Tags math, number theory	1800	x6101
1845F	Swimmers in the Pool dp, fft, math, number theory	2800	x359
1845A	Forbidden Integer constructive algorithms, implementation, math, number theory	800	x25571
1844G	Tree Weights bitmasks, constructive algorithms, data structures, dfs and similar, implementation, math, matrices, number theory, trees	3000	x673
1844D	Row Major constructive algorithms, greedy, math, number theory, strings	1400	x11916
1838C	No Prime Differences constructive algorithms, math, number theory	1400	x13818
1835D	Doctor's Brown Hypothesis dfs and similar, graphs, math, number theory	2900	x458
1834E	MEX of LCM binary search, data structures, implementation, math, number theory	2300	x2113
1830C	Hyperregular Bracket Strings combinatorics, greedy, hashing, math, number theory, sortings	2400	x1569
1828B	Permutation Swap math, number theory	900	x21531
1826C	Dreaming of Freedom greedy, math, number theory	1300	x13066
1826B	Lunatic Never Content math, number theory	1100	x16438
1823C	Strongly Composite greedy, math, number theory	1300	x11892
1822G2	Magic Triples (Hard Version) brute force, data structures, math, number theory	2200	x2356
1822G1	Magic Triples (Easy Version) brute force, data structures, math, number theory	1700	x6763
1816A	Ian Visits Mary constructive algorithms, geometry, number theory	800	x17071
1815E	Bosco and Particle dp, math, number theory, strings	3100	x332
1812F	Factorization *special problem, number theory		x968
1812D	Trivial Conjecture *special problem, constructive algorithms, math, number theory		x4356
1811E	Living Sequence binary search, dp, math, number theory	1500	x11825
1810B	Candies constructive algorithms, math, number theory	800	x17281
1806F1	GCD Master (easy version) greedy, math, number theory, sortings	2900	x342
1804C	Pull Your Luck brute force, greedy, math, number theory	1500	x11746
1801F	Another n-dimensional chocolate bar dp, math, meet-in-the-middle, number theory	2700	x554
1798F	Gifts from Grandfather Ahmed dp, math, number theory	2500	x474

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